7717-76-2

Usage

Uses

Used in Polymer Production:
4-(3,4-dicarboxyphenoxy)benzene-1,2-dicarboxylic acid is used as a monomer in the production of polymers, specifically for manufacturing high-performance resins and coatings. Its heat resistance and electrical insulation properties make it a valuable component in this application.
Used in Flame-Retardant Materials:
In the Flame-Retardant Industry, 4-(3,4-dicarboxyphenoxy)benzene-1,2-dicarboxylic acid is used as a key ingredient in the production of flame-retardant materials. Its chemical structure contributes to the fire-resistant properties of these materials, enhancing safety in various applications.
Used as a Corrosion Inhibitor in Metal Coatings:
In the Metal Coating Industry, 4-(3,4-dicarboxyphenoxy)benzene-1,2-dicarboxylic acid serves as a corrosion inhibitor. Its presence in metal coatings helps protect against corrosion, extending the lifespan and durability of metal surfaces.
Overall, 4-(3,4-dicarboxyphenoxy)benzene-1,2-dicarboxylic acid plays a crucial role in the development of advanced materials for multiple industries, including polymer production, flame-retardant materials, and metal coatings, due to its unique properties and applications.

Upstream product

• 1823-59-2 4,4'-oxydiphthalic dianhydride 
• 41663-84-7 4-nitro-N-methyl-phthalimide 
• 27507-54-6 oxo-bis-4,4'-(N-methylphthalimide) 
• 610-27-5 4-nitrophthalic acid 
• 118-45-6 4-chlorophthalic anhydride 

Downstream Products

• 1823-59-2 4,4'-oxydiphthalic dianhydride 
• 33734-37-1 4,4'-oxybis(N-phenylphthalimide) 
• 1243264-57-4 C₃₂H₄₀N₂O₅ 

Relevant academic research and scientific papers

Preparation method of 4, 4'-diphenyl ether tetracarboxylic dianhydride

The invention provides a preparation method of 4, 4'-diphenyl ether tetracarboxylic dianhydride, which comprises the following steps: S1, dissolving 4-nitrophthalic acid in a solvent, and heating for dehydration; S2, adding a molybdenum salt catalyst, a halogen promoter and carbonate into the reaction liquid obtained in S1, and carrying out etherification coupling reaction to obtain a 4, 4'-diphenyl ether tetracarboxylic acid crude product; S3, refining and dehydrating the crude product obtained in S3 to obtain 4, 4'-diphenyl ether tetracarboxylic dianhydride; wherein the weight ratio of the 4-nitrophthalic acid to the solvent to the molybdenum salt to the halogen is 1: (2-3.5): (0.02-0.05): (0.1-0.3); and the molar ratio of the 4-nitrophthalic acid to the carbonate is 1: (0.55-0.75). The molybdenum powder serves as the catalyst, the halogen serves as the cocatalyst, the conversion rate of the 4-nitrophthalic acid is larger than 99%, the molar yield of the 4, 4'-diphenyl ether tetracarboxylic acid crude product is larger than 85%, the method is unique, the technological process is simple, operation is easy, the yield is high, the cost is low, and the production efficiency and economic benefits are high.

Preparation method of 3,3 ’, 4,4 ’ - diphenyl ether tetracarboxylic dianhydride (by machine translation)

The refined product is subjected to, heating 3,3',4,4' - and drying dehydration to obtain the refined product of formula I ;(2) as shown :(1) in the: formula, I after heating the purified product by, N - heating, heating, refluxing, heating, refluxing, heating, refluxing, heating and, refluxing the non,protonic polar solvent,(3) ;(4), 3,3',4,4' . (by machine translation)

METHOD OF PURIFYING DIANHYDRIDES, THE DIANHYDRIDES FORMED THEREBY, AND POLYETHERIMIDES FORMED THEREFROM

A method for purifying an oxydiphthalic anhydride comprises diluting a first mixture comprising an oxydiphthalic anhydride, a solvent, a catalyst, and an inorganic salt with a solvent, to provide a second mixture having a solids content of 10 to 30 percent based on total weight of the second mixture; filtering and washing the solids of the second mixture at a temperature below the crystallization point temperature of the oxydiphthalic anhydride to provide a third mixture; hydrolyzing the third mixture by adding water and a water-soluble acid to form a fourth mixture; heating the fourth mixture; then cooling to provide a solid-liquid mixture, optionally decanting a portion of the liquid, re diluting the remaining solid-liquid mixture, then filtering to provide a solid component; washing the solid component with water to provide a fifth mixture of oxydiphthalic tetra acid and water; ring closing the oxydiphthalic tetra acid to provide oxydiphthalic anhydride, and filtering the oxydiphthalic anhydride.

Method of Purifying Dianhydrides, the Dianhydrides Formed Thereby, and Polyetherimides Formed Therefrom

A method for purifying an oxydiphthalic anhydride comprises diluting a first mixture comprising an oxydiphthalic anhydride, a solvent, a catalyst, and an inorganic salt with a solvent, to provide a second mixture having a solids content of 10 to 30 percent based on total weight of the second mixture; filtering and washing the solids of the second mixture at a temperature below the crystallization point temperature of the oxydiphthalic anhydride to provide a third mixture; hydrolyzing the third mixture by adding water and a water-soluble acid to form a fourth mixture; heating the fourth mixture; then cooling to provide a solid-liquid mixture, optionally decanting a portion of the liquid, rediluting the remaining solid-liquid mixture, then filtering to provide a solid component; washing the solid component with water to provide a fifth mixture of oxydiphthalic tetraacid and water; ring closing the oxydiphthalic tetraacid to provide oxydiphthalic anhydride, and filtering the oxydiphthalic anhydride.

Method of purifying dianhydrides

Disclosed herein is a method for purification of dianhydrides comprising a substantial amount (10000 ppm or more) of at least one metal salt. In one aspect the method is useful for the purification of dianhydrides prepared by the reaction of a halophthalic anhydride with a metal carbonate and may be optionally catalyzed by a phase transfer catalyst. The purification of the dianhydrides may be accomplished by hydrolyzing the dianhydride metal salt mixture directly to a tetraacid with an inorganic acid, followed by separating the impurities from an aqueous phase, and subsequently heating the tetraacid to effect ring closure to form a purified dianhydride having less than 50 parts per million metal halide and lower levels of other residual impurities. In one aspect the method is highly effective in removing phase transfer catalyst impurities such as hexalkylguanidinium halides initially present in the dianhydride undergoing purification.

Method of purifying dianhydrides

A method of preparing a purified dianhydride is provided where said method comprises the steps of preparing a first mixture comprising water, at least one inorganic acid, and at least one dianhydride, said dianhydride comprising at least one impurity which is soluble in aqueous acid heating said first mixture until substantially all of said dianhydride is converted to a tetraacid comprised in a second mixture; filtering at least a portion of said second mixture to provide a solid tetraacid and a filtrate, said filtrate comprising at least a portion of said impurity; and heating the tetraacid provided in a solvent with concurrent distillation of water to provide a third mixture comprising a purified dianhydride and a solvent.

Method of purifying dianhydrides

A method of preparing a purified dianhydride is provided comprising the steps of preparing a first mixture comprising water, at least one inorganic acid, and at least one dianhydride, said dianhydride comprising at least one impurity which is soluble in aqueous acid; heating said first mixture until substantially all of said dianhydride is converted to a tetraacid comprised in a second mixture; filtering at least a portion of said second mixture to provide a solid tetraacid and a filtrate, said filtrate comprising at least a portion of said impurity; and heating the tetraacid provided in a solvent with concurrent distillation of water to provide a third mixture comprising a purified dianhydride and a solvent.

Process for the preparation of oxydiphthalic anhydride and acyloxyphthalic anhydrides

A method for the preparation of acyloxyphthalic anhydride or oxydiphthalic anhydride which comprises the reaction of a halophthalic anhydride with an alkali metal salt and at least a catalytically effective amount of an acid or acid derivative selected from the group consisting of benzoic acids, substituted benzoic acids, benzoic acid salts or substituted benzoic acid salts, and hydrolyzable benzoyl esters, and hydrolyzable substituted benzoyl esters, alkyl carboxylic acids, hydrolyzable esters of alkyl carboxylic acids, and salts of alkyl carboxylic acids. The process may be conducted without solvent, in a polar solvent or in a non-polar solvent using a phase transfer catalyst.

Process for, respectively, the production and purification of dicarboxylic and polycarboxylic acid anhydrides

A method of preparation and/or purification of acid anhydrides is disclosed. Dicarboxylic or polycarboxylic acids contained in the anhydrides to be treated, are dehydrated in an organic solvent in the presence of activated carbon.

Method for making aromatic bis(ether dicarboxylic acid)s

A method is provided for making aromatic bis(ether dicarboxylic acid)s, such as 2,2-bis[4(3,4-dicarboxyphenoxy)phenyl] propane. The corresponding aromatic bis(etherimide) is hydrolyzed in base to produce a tetraacid salt which is directly acidified with concentrated mineral acid such as sulfuric acid. The resulting aqueous mixture containing a paste is heated to produce the aromatic bis(ether dicarboxylic acid) in ready filterable form.